Resealing is the planned, whole-lantern version of a leak repair: we cut out the old, failed sealant, clean every joint back to a sound surface and reseal the cappings, ridge and eaves with materials that suit the frame. We carry out roof lantern resealing across Mid Glamorgan, with a guide price from your photos and a fixed price in writing before any work starts.

Signs you need roof lantern resealing
- Black mould or dirt lines trapped in old silicone
- Sealant applied over sealant from previous patch repairs
- A lantern that is 8–15 years old and has never been maintained
What usually causes it?
Sealant past its life
Exposed sealant on a roof takes UV, frost and constant expansion and contraction. It hardens, loses grip and pulls away from the glass.
Wrong product used
General-purpose or acetoxy silicone can fail early on some frames and coatings. Glazing joints need a low-modulus, compatible sealant.
Roof lanterns in Mid Glamorgan
Western and upland parts of the UK get more rain and more wind-driven rain than the east, and that's what finds weak cappings and blocked eaves first. Lanterns here benefit from a check of the bars on the most exposed face and a clear eaves channel before winter.
What should you expect to pay for roof lantern resealing in Mid Glamorgan?
Typical range: £245–£495 ex VAT, which is £294–£594 with VAT, per lantern. Towers or scaffold, where needed, are priced into the quote. Your fixed price is confirmed in writing before any work starts.
Do you need permission in Wales?
Most lantern repairs in Wales need no approval at all. Where a job turns into a replacement, the Building Regulations 2010 (as applied in Wales) apply and we confirm how the work will be signed off before we start. Listed buildings in Wales need listed building consent from the local planning authority for alterations, with Cadw guidance on historic buildings; check with the council before changing a lantern on a listed property.
How does it work?
- Send photosWhatsApp or upload a few photos and tell us when it leaks.
- Guide priceWe reply with a guide price and whether a visit is needed.
- Fixed price in writingYou approve the price and the date before anything starts.
- Repair and testWe fix what's failed, water-test where it matters, and send photos.
Roof lantern resealing in Mid Glamorgan: questions
How much does it cost to reseal a roof lantern?
A standard-size lantern on a single-storey extension is usually £245–£495 ex VAT. Larger lanterns, difficult access or gasket replacement add to that, and you get the fixed price in writing first.
Can you match the colour of my frame?
We use sealants in common frame colours such as anthracite grey, black and white, and match as closely as the range allows.
Which towns in Mid Glamorgan do you cover?
All of Mid Glamorgan, including Bridgend, Rhondda, Tonypandy, Merthyr Tydfil, Pontypridd, Aberdare. Rural and remote addresses are covered by arrangement.
How do I get a price for roof lantern resealing in Mid Glamorgan?
Send a few photos of the lantern and the problem with your postcode, by WhatsApp or the form. We reply with a guide price and confirm the fixed price in writing before any work starts.
Other repairs in Mid Glamorgan
- Cracked lantern glass replacement in Mid Glamorgan
- Slipped glass panel repairs in Mid Glamorgan
- Solar control and self-cleaning glass upgrades in Mid Glamorgan
- Aluminium roof lantern repairs in Mid Glamorgan
- Opening vent and actuator repairs in Mid Glamorgan
- Commercial roof lantern repairs in Mid Glamorgan
Nearby areas
- Roof lantern resealing in South Glamorgan
- Roof lantern resealing in West Glamorgan
- Roof lantern resealing in Gwent
- Roof lantern resealing in Powys
- Roof lantern resealing in Dyfed
More about roof lantern resealing · All roof lantern repairs in Mid Glamorgan